Colorado’s mountain snowpack measured 109% of the 30-year norm on Monday after lagging earlier this winter, setting up potentially healthy water supplies.
March snowstorms bolstered the snowpack, which typically peaks in mid-April before melting intensifies.
“We’re sitting pretty right now,” National Weather Service meteorologist Caitlyn Mensch said. “We’re above 100% everywhere, which is positive to see as we head into spring.”
The snow in Colorado’s mountain river basins melts gradually, depending on temperatures, trickling into creeks and rivers that flow into water storage reservoirs. On Jan. 5, the overall snowpack in western Colorado hovered around 70% of the norm after months of relatively dry conditions, according to the U.S. Department of Agriculture’s snow survey data.
On Monday, those federal measurements of “snow water equivalent” — the amount of water held in the snow — showed snowpack at 108% of the norm in the closely-watched Upper Colorado River Basin, a crucial source for 40 million people in seven states and the nation’s agriculture.
The snowpack in the South Platte River Basin, which supplies metro Denver and the farms and ranches across northeastern Colorado, has reached 114% of the norm, data shows. Before last week’s heavy snow along the Front Range, that basin was at 96% of the norm.
In the Arkansas River Basin that supplies farms on the southeastern Colorado plains, the snowpack measured 111%.
“The recent storm was especially big for areas east of the Continental Divide. The Arkansas basin in southern Colorado went from well below to well above average just from this single storm,” state climatologist Russ Schumacher said from the Colorado Climate Center at Colorado State University.
“Getting big upslope storms in the spring is consistent with the ongoing El Niño,” Schumacher said, referring to the Pacific Ocean patterns that influence weather. “El Niño years often have near average to below-average snowfall through the heart of winter but then things pick up in March and April.”
The Upper Rio Grande River in southern Colorado had a snow-water equivalent of 101%, data shows. Southwestern Colorado mountains had a combined snow-water level of 103% of the norm in the San Miguel, Dolores, Animas, and San Juan river basins. The Gunnison River Basin was at 103%; the Yampa and White river basins at 113%; and the Laramie and North Platte basin at 106%.
Much of the land in southwestern Colorado remained dry, U.S. Drought Monitor data shows. Parts of Saguache, Alamosa, Costilla, and Conejos counties in the San Luis Valley were classified as in severe drought.
National Weather Service forecasters on Monday were anticipating more snow on Sunday.
